The use of this improper grammar most likely branched off from the contraction mine's (or mine is). For example "Your ice cream is vanilla, and mine's chocolate." Somewhere along the line, someone forgot that "is" is already part of "mine's" and they made the mistake of saying things like "Mine's is strawberry" or (Mine is is strawberry).
Eventually, the singular form of the word was completely dropped from the vocabulary, and "mine's" became used to show all ownership, even when adding "is" is inapplicable.

Edgar: "Hey Reggie, I just got my new phone today."
Reggie: "Yea, I think I'm gonna buy mines when I get my next paycheck, dawg."

1. A word used to tell people that something belongs to you.
2. A place, usualy a underground tunnel where ores or precius stones are being gathered and shipped off.
3.(to mine)The act in MMORPG's to keep gathering the same resource.
4.A device made by/for the military, it is a bomb, usualy flat and cilinder shaped and hard to spot becouse of camouflage coloring, that has some kind of trigger to detect if a person or vehicle is near, they are bad, bad things becouse after a war, the ones who placed them dont clean them up and they stay there until a random person walks on it and dies/loses limbs.

1.That bike is mine, not yours.
2.The diamonds mined there where huge.
3.Where can i mine fish?
4.There are special robots and machines that can clearn an area of mines quicly.